
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }
        /* 让容器的宽度和高度充满全屏 */
        html, body{
            width: 100%;
            height: 100%;
        }
        body{
            background-color: pink;
            display: flex;
            flex-direction: row;
            align-items: center;
            justify-content: center;
        }
        .heart{
            width:200px;
            height:200px;
            background-color: red;
            position:relative;
            transform: rotate(45deg);
            animation:heartbit 1s infinite alternate; /* 设置动画 */
            box-shadow: 0 0 30px red;
        }
        .heart::before{
            content:"";
            width:200px;
            height:100px;
            background-color: red;
            position: absolute;
            left:0;
            top:-99px;
            border-radius: 100px 100px 0 0;
            box-shadow: 0 0 30px red;
        }
        .heart::after{
            content:"";
            width:100px;
            height:200px;
            background-color: red;
            position: absolute;
            left:-99px;
            top:0;
            border-radius: 100px 0 0 100px;
            box-shadow: 0 0 30px red;
        }

        /* 实现动画，让心跳起来 */
        @keyframes heartbit{
            0%{
                transform: rotate(45deg) scale(0.6);
            }
            /* 25%{
                transform: rotate(45deg) scale(0.8);
            }
            50%{
                transform: rotate(45deg) scale(1);
            }
            75%{
                transform: rotate(45deg) scale(1.3);
            } */
            100% {
                transform:rotate(45deg) scale(1.4);
            }
        }


    </style>
</head>
<body>
    <div class="heart"></div>
</body>
</html>